servevolleyR

Simulate many matches between two players, given a number of parameters, that include probability of each player winning a point on their first serve, on their second serve, and the probability that their first serve will go in. This function returns a detailed list with data about the sets and games within each simulated match.

Usage

simMatches(n = 1000, pA, pB, sets = c(3, 5), tiebreaks = TRUE,
           finalSetTiebreak = FALSE, players = c("A", "B"),
           p2A = NULL, firstServeA = NULL,
           p2B = NULL, firstServeB = NULL,
           .progress = "none")

Arguments

param	details
n	number of simulations (default is 1000)
pA	probability of player A winning point on their first serve
pB	probability of player B winning point on their first serve
sets	number of sets (3 or 5)
tiebreaks	play tiebreaks in the event the set reaches 6 games all (default = TRUE)
finalSetTiebreak	play a final set tiebreak if sets and games are tied, otherwise keep playing
players	player names (vector of length 2)
p2A	probability of player A winning point on their second serve
firstServeA	probability of player A’s first serve being in
p2A	probability of player B winning point on their second serve
firstServeB	probability of player B’s first serve being in
.progress	`plyr`’s progress bar

Return

Unlike using replicate on simMatch, using simMatches will return a detailed list, containing data about the simulated matches rather than just the results of those simulations.

Methods

There are a number of generic methods available for an object returned by simMatches, these are print, summary and plot, example use is show below.

Example

egMatches <- simMatches(n = 100, sets = 3,
                        pA = .78, pB = .70,
                        p2A = .56, firstServeA = .67,
                        p2B = .6, firstServeB = .7)

The object egMatches has a class of svR_matches which comes with a few methods

egMatches

## 
## Simulation of 100 matches:
## 
## Player A (A) won 0.67 of matches.
## 
## Server Probabilities:
##  player    p   p2 firstServe
##       A 0.78 0.56       0.67
##       B 0.70 0.60       0.70

summary(egMatches)

## 
## Simulation of 100 matches:
## 
## Player A (A) won 0.67 of matches.
## 
## Server Probabilities:
##  player    p   p2 firstServe
##       A 0.78 0.56       0.67
##       B 0.70 0.60       0.70
## 
## 
##        playerB
## playerA    0    1    2
##       0           0.12
##       1           0.21
##       2 0.41 0.26

plot(egMatches)

Using `simMatches`

The returned list can also be entered into the function simDf which will convert the simulated matches into a dataset, containing data about each of the simulations, including data going all the way down to the individual games. egMatches, created above, contains 100 simulations, which produces a dataset of dimensions , each simulation will produce a different sized dataset, a large number of simulations will obviously produce a much larger dataset, and will take longer for simDf to create the dataset.

df <- simDf(egMatches)
head(df)

##   simNo playerA playerB mA mB result setNo pA pB setA setB set_res gameNo
## 1     1       A       B  1  2      0     1  A  B    6    3       1      1
## 2     1       A       B  1  2      0     1  A  B    6    3       1      2
## 3     1       A       B  1  2      0     1  A  B    6    3       1      3
## 4     1       A       B  1  2      0     1  A  B    6    3       1      4
## 5     1       A       B  1  2      0     1  A  B    6    3       1      5
## 6     1       A       B  1  2      0     1  A  B    6    3       1      6
##   serving    p   p2 firstServe game_res server returner
## 1       A 0.78 0.56       0.67        1      5        3
## 2       B 0.70 0.60       0.70        1      4        0
## 3       A 0.78 0.56       0.67        1      4        2
## 4       B 0.70 0.60       0.70        1      4        1
## 5       A 0.78 0.56       0.67        1      4        0
## 6       B 0.70 0.60       0.70        1      4        0

The dataset contains the following variables:

variables	about
simNo	simulation number
playerA	player A (who started the match serving)
playerB	player B (who started the match returning)
mA	sets won by player A
mB	sets won by player B
result	match result, (1 if player A wins, 0 otherwise)
setNo	set number
pA	player A (who started the set serving)
pB	player B (who started the set returning)
setA	games won by player A
setB	games won by player B
set_res	set result (1 if player A wins, 0 if player B wins)
gameNo	game number in set
serving	player serving
p	probability of server winning a point on their first serve
p2	probability of server winning a point on their second serve
firstServe	probability of first serve being in
game_res	game result (1 if server wins, 0 if returner wins)
server	number of points won by server in service game
returner	number of points won by returner in service game